Well packer apparatus

ABSTRACT

A well packer apparatus having a mandrel movable between extended and contracted positions within an anchor body that carries holddown slips, an internal bypass passage that is opened and closed by a balanced valve sleeve movable longitudinally relative to the mandrel and the anchor body, first coengageable elements to prevent operation of said slips when the mandrel ix extended, second coengageable means to move said valve sleeve to closed condition as the mandrel is moved to contracted position, and a mechanical interlock to releasably secure the mandrel in contracted position.

United States Patent McGill [451 Feb. 29, 1972 [54] WELL PACKERAPPARATUS [72] inventor: Howard L. McGill, Houston, Tex.

[73] Assignee: Schlumberger Technology Corporation,

New York, NY.

[22] Filed: Apr. 7, 1970 [2]] Appl. No.: 26,384

[52] US. Cl. ..l66/120, 166/129 [5 1] Int. Cl ..E2lb 33/129 [58] Fieldof Search ..166/120, 129, I34

[56] References Cited UNITED STATES PATENTS 3,223,169 12/1965 Roark..l66/l29 X 3,112,795 12/1963 Keithahn 166/120 3,338,308 8/1967 Ellistonetal. ..l66/120 McGill "166/120 Young ..l66/l20 X Primary Examiner-DavidH. Brown Attorney-Emest R. Archambeau, Jr., Donald H. Fidler, David L.Moseley, Edward M. Roney and William R. Sherman [57] ABSTRACT A wellpacker apparatus having a mandrel movable between extended andcontracted positions within an anchor body that carries holddown slips,an internal bypass passage that is opened and closed by a balanced valvesleeve movable longitudinally relative to the mandrel and the anchorbody, first coengageable elements to prevent operation of said slipswhen the mandrel ix extended, second coengageable means to move saidvalve sleeve to closed condition as the mandrel is moved to contractedposition, and a mechanical interlock to releasably secure the mandrel incontracted position.

20 Claims, 10 Drawing Figures PAIENTEDFEBZS I972 3,545 334 SHEET 1 BF 5FIG. 18

Howard L, McGi/l INVENTOR BY flwzA w ATTORNEY PATENTEDFEB 2 9 I972 SHEET2 OF 5 Howard L. McGi/l ATTORNEY FIG. III

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sum 3 OF 5 FIG. 2A FIG.2B

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ATTORNEY SHEET 5 [IF 5 IN VE N TOR Howard L. McGi/l BY [44411 W FIG.3B

ATTORNEY WELL PACKER APPARATUS This invention relates generally to wellpackers used in well bores, and more specifically to a new and improvedretrievable packer that is adapted to be installed in a producing welland anchored against movement due to fluid pressure in eitherlongitudinal direction.

In well production operations where a packer that isolates the producinginterval may be subjected to pressure differentials acting in eitherdirection, it is fairly common practice to anchor the packer againstdownward movement by a slip and expander combination that is set by theweight of the production string that extends from the packer to the topof the well. An anchor system that responds to greater fluid pressurebelow the packer is used to anchor the packer against upward movement.The packer may also employ an internal bypass passage that is closed offwhen the tool is set by a valve that is actuated by downward movement ofthe packer mandrel. A well packer having a particularly successfulanchor and bypass arrangement of this type is shown in my US. Pat. No.3,399,729, issued Sept. 3, 1968. However, the packer shown in thispatent is primarily adapted for well service operations such as squeezecementing, hydraulic fracturing and acidizing.

In production operations, it is considered to be desirable to provide arelatively long travel or stroke mandrel to expedite spacing outprocedures during installation of the production string of tubing. Moreparticularly, the packer is run in and set at a precise location abovethe production interval, and the elevation of the packer should not bedisturbed during installation of surface flow control equipment such asa Christmas tree. Since the installation of such equipment may require asubstantial amount of vertical pipe movement in order to set the pipe inhangers orto secure bolted flanges, a relatively long mandrel travel maybe necessary to insure that the location of the packer anchor is notmoved during surface manipulations of the pipe string.

Moreover, after a production packer has been in service over an extendedperiod of time and it is necessary to remove it from the well forworkover operations or the like, difficulty can be encountered inunseating the packing elements. When this occurs, a long stroke mandrelenables a jarring action to be applied by working the production stringupwardly and downwardly, similar in nature to the use of a bumper sub.

In situations where a greater pressure exists below the packer than inthe annulus above it, the pressure acts in opposition to the weight ofthe production string which supplies the setting force for the packer.The greater pressure is used to actuate the holddown slips to preventupward movement of the packing elements, however upward movement of themandrel is undesirable because such movement may open the bypass valveand equalize pressures. Accordingly it has become common practice toemploy a hydraulic balance piston arrangement to counterbalance theupward force on the mandrel due to greater pressure below the packer.Such balancing features can tend to unduly complicate the structure ofthe packer, and in production packers that normally remain in a well foran extended period of time, seal deterioration can occur and causeleakage. Thus it is considered to be desirable to provide a mechanicalinterlock that functions to prevent upward movement of the mandrel, amechanical arrangement being more reliable under adverse conditions andaffording in general a more simplified structural arrangement than ahydraulic system. As a further feature of the present invention, thevalve that closes the internal bypass passage is hydraulically balancedto reduce the unbalanced areas that are available for the greaterpressure below the packer to act upon, thereby reducing to a minimum theupward force on the mandrel that is produced by such greater pressure.The mandrel is movable longitudinally within limits with respect to thevalve in accordance with the long stroke capability of the mandrel.

It is accordingly an object of the present invention to provide a newand improved well packer apparatus that can be anchored against movementin either direction, and which employs a long stroke mandrel tocompensate for spacing procedures during installation in a well.

Another object of the present invention is to provide a new and improvedwell packer apparatus having a bypass valve that is closed by downwardmovement of the packer mandrel, together with a mechanical interlock toabsolutely prevent upward movement of the mandrel due to pressure frombelow.

Yet another object of the present invention is to provide a new andimproved well packer apparatus having an internal bypass passage that isclosed when the packer is set by a balanced valve.

These and other objects are attained in accordance with the concepts ofthis invention by a well packer apparatus comprising a mandrel that istelescopically disposed within an anchor body having packing means toseal off a well bore. A lower slip and expander combination is used toanchor against downward movement, and an upper slip and expandercombination carried by the anchor body is responsive to greater fluidpressure below the packer to anchor against upward movement. A bypasspassage extends along the mandrel inside the packing and terminatesabove the packing in side ports below the upper slips. The passage isopened and closed by a valve sleeve that is movable longitudinallyrelative to the mandrel between limit positions defined by oppositelydisposed shoulders on the mandrel.

The longitudinal movement enables a long stroke mandrel, and when themandrel is in its upper or running position, coengageable meansincluding one of the mandrel shoulders is provided to positively retainthe holddown slips in retracted positions. Downward movement of themandrel as the packer is set releases the coengageable means, and causesthe other of the mandrel shoulders to engage the valve sleeve and moveit to closed position with respect to the bypass passage. The valvesleeve has equal and oppositely disposed transverse areas exposed tofluid pressure to balance the valve sleeve. A mechanism is provided tolock the mandrel to the anchor body in its lower position, in order toprevent fluid pressure below the packer from lifting the mandrel andaccidentally opening the bypass.

The present invention has other features, objects and advantages whichwill become more readily apparent in connection with the followingdetailed description of several embodiments, taken in conjunction withthe accompanying drawing, in which:

FIGS. lA-lD are longitudinal sectional views with portions in sideelevation, of one embodiment of a well packer in accordance with thisinvention with parts in running-in positions;

FIGS. 2A-2D are views similar to FIGS. lA-lD except showing the packerparts in their relative positions when set in a well casing; and

FIGS. 3A and 3B are longitudinal sectional views with portions in sideelevation of a modified form of the present invention, again with partsin running-in positions.

Referring initially to FIGS. lA-lD,- one embodiment of a well packer 10in accordance with the concepts of the present invention includes amandrel 11 that is telescopically disposed within an anchor body 12having an upper section 13 and a lower section 14. The upper end of theupper section 13 is closed by an annular cap 15 that is sealed withrespect to the mandrel 11 by a seal ring 16. The mandrel 11 is showforeshortened for convenience of illustration, and is actually elongatedso that a substantial amount of telescoping movement is available forpurposes to be described'hereinafter. A locking sub 17 is threadedlyconnected to the cap 15 and has diagonally opposed jay-slots 18 that areadapted to receive opposed lugs 19 on the mandrel collar 20 in order tolock the mandrel 11 in its lowermost position. The slots 17 haveinclined wall surfaces 21 to automatically guide the lugs 19 into theclosed portions 21 of the slots.

The lower end of the anchor body 12 is connected to an upper abutmentring 22 (FIG. 1C) that is in turn connected to an annular compressionsleeve 23. The compression sleeve 23 carries a plurality of annularelastic packing elements 24 which may be separated by metallic spacerrings 25. A lower abutment 26 is slidable on the compression sleeve 23,and constitutes the upper end portion of a slip expander 27. The sleeveportion 28 of the expander 27 is corotatively secured to the compressionsleeve 23 by a typical spline connection 29, and has a cone portion 30with downwardly and inwardly inclined outer surfaces 31.

A plurality of normally retracted slips 34 (FIG. 1D) having toothedouter surfaces 35 and inclined inner surfaces 36 are pivotally attachedto a drag assembly indicated generally at 37. The slip and drag assemblyto be described immediately hereafter is only to be considered asillustrative and not in a limiting sense, since other well known anchorassemblies could be used. The drag assembly 37 includes an annular cageor housing 38 having circumferentially spaced, longitudinal slots 39which receive rectangularly shaped friction drag blocks 40. Between eachdrag block 40 and the cage 38 are coil springs 41 that urge the blocksradially outwardly into friction engagement with a well casing. Eachblock 40 has end portions or flanges 42 (only one end shown) to retainthe block in the cage 38. Associated with each drag block 40 is arespective slip element 34 having a head 43 and a stem 44. Each dragblock 40 has a slot 45 which receives the stem 44, and a pin 46pivotally interconnects the stem to the drag block. A coil spring 47 ispositioned between the cage 38 and a tang 48 on each stem 44 to urge thetang outwardly and thereby pivot the slip head 43 inwardly toward themandrel 1 l A gauge ring 50 is secured to the lower end of the cage 38by studs 51 or the like, and has an inwardly projecting lug 52 thatcoacts with a typical jay-slot 53 formed on the exterior of the mandrel11 in order to couple the drag assembly 37 to the mandrel during runningand retrieving. The mandrel 1 1 can be manipulated in a conventionalmanner, for example by elevating the mandrel and then lowering it whileapplying right-hand torque, to release the lug 52 from the jay-slot 53so that the mandrel can be moved downwardly relative to the dragassembly to set the packer 10. Of course it will be appreciated thatthese parts could be reversed so that the lug is on the mandrel 11 andthe jay-slot is in the cage or housing 38. A tie sleeve 54 connected tothe cage 38 extends upwardly within the expander cone 30 and has anenlarged shoulder portion 55 engaging in an internal annular recess 56to limit upward movement of the slip expander 27 relative to the dragassembly 37.

Referring again to FIG. 1C, the compression sleeve 23 has a larger innerdiameter than the outer diameter of the adjacent mandrel portion 58 toprovide an annular fluid bypass passage 59 that extends from lateralports 60 in the sleeve portion 28 of the expander 27 to lateral ports 61through the wall of the lower section 14 of the anchor body 12. Thebypass passage 59 is open during running and retrieving but is adaptedto be closed off by an annular valve sleeve 62 having a seal assembly 63that is engageable with a seal surface 64 on a seat ring 65 when thevalve sleeve is shifted downwardly as will subsequently be described.The valve sleeve 62 is coupled for limited longitudinal movementrelative to the mandrel 11 through the provision of a split drive ring66 (FIG. 18) that is slidable relative to the mandrel between limitpositions defined by an upwardly facing shoulder 67 and a downwardlyfacing shoulder 68. A seal sleeve 69 is connnected to the valve sleeve62 by a collar 70 and extends upwardly along the mandrel 11, the drivering 66 being confined within an internal recess 71 in the collar andbetween the opposed end surfaces of the valve and seal sleeves. Asubstantial coil spring 72 (FIG. 1C) surround the valve sleeve 62 andrests on the upper end surface of the valve seat ring 65. The upper endof the spring is aligned to be engaged by the lower end surface of thecollar 70 for purposes to be described hereafter.

The upper section 13 of the anchor body 12 has a plurality of radiallydisposed windows 75 that carry holddown slips 76 having toothed outersurfaces 77 and inner inclined surfaces 78. The slips 76 are adapted tobe shifted outwardly by an expander assembly 79 that includes anexpander piston 80 having expander inserts 81 mounted on stepped outersurfaces thereof and attached thereto by screws 82 or the like. Theinserts 81 have outer inclined surfaces 83 to wedge the slips 76outwardly, and a sliding connection is provided by a dovetail spline 84that fits within a mating groove 85 on a respective slip. The lower endof each slip 76 is provided with a tongue 86 that fits slidably within acompanion groove 87 to guide the slip outwardly, the groove beingprovided in a thickened section 88 of the anchor body 12. The section 88is sealed with respect to the seal sleeve 69 by a seal ring 89.

Downward movement of the expander assembly 79 will result in outwardshifting of the slips 76 into gripping contact with a well casing wall,and upward movement will cause inward retraction. During running andretrieving of the the packer 10, the lower shoulder 67 on the mandrel 11engages the drive ring 66 in order to retain the seal sleeve 69 in itsupper position. The seal sleeve 69 also has a shoulder 90 that engages ashoulder 91 on the expander piston 80 to positively retain the expanderassembly 79 in its upper position and thus the slips 76 in theirretracted positions. When the mandrel 11 is moved downwardly duringsetting of the packer 10, the parts are no longer retained, and downwardmovement of the expander assembly 79 will occur when the pressure offluids 7 below the packer 10 is greater than the pressure of fluids inthe annulus above the packer, as follows. The expander piston 80 issealed with respect to the upper anchor body section 12 by a seal ring92, and with respect to the seal sleeve 69 by a seal ring 93. Thedownwardly facing transverse surfaces of the expander piston 80 aresubject to the pressure of fluids in the well annulus via the windows 75in the anchor body 12. The

upwardly facing transverse surfaces of the expander piston 80 aresubject to the pressure of fluids in the well bore below the packer viaannular clearance spaced 94 and inside the seal sleeve 69 and the valvesleeve 62 respectively, and via the bypass passage 59 and the lowerbypass ports 60. Accordingly, with the valve sleeve 62 in closedposition, a greater fluid pressure below the packer will act downwardlyon the difference in transverse areas circumscribed by the seals 92 and93 to force the expander assembly 79 downwardly and the slips 76outwardly. Of course a greater fluid pressure in the annulus willretract the slips 76.

One feature of the present invention resides in the fact that theassembly constituted by the valve sleeve 62 and the seal sleeve 69 isbalanced with respect to fluid pressure. This is accomplished by sizingthe parts such that the seal diameter for the valve seal 63 is equal tothe seal diameters for the seals 89 and 93. Thus arranged, fluidpressure acts with equal force on oppositely disposed transversesurfaces of the members, whether the pressure is greater below thepacker or in the annulus above the packer. Accordingly, a greaterpressure below the packer will not tend to move the valve to openposition, nor will a greater pressure in the annulus tend to hold thevalve in closed condition.

In operation, the packer 10 is connected to the lower end of a pipestring and run into the well casing with the parts in the relativepositions shown in FIGS. lA-D. The drag assembly 37 and the slips 34 arefixed with respect to the mandrel l l by engagement of the lug 52 with aclosed portion 53 of the jay-slot 53. The drag blocks 40 slide infrictional engagement with the casing, and the slip heads 43 are pivotedinwardly' in their normally retracted positions by the coil springs 47.The packing elements 24 are in relaxed condition, and fluids present inthe well bore can bypass between the packing and the well casing wall,as well as through the lower ports 60, bypass passage 59 and the upperports 61. The lower shoulder 67 on the mandrel "1 1, through the drivering 66, supports the valve sleeve 62 and the seal sleeve 69 in an upperposition, and the upper end of the seal sleeve can engage the cap 15 tohold the anchor body 12 and the compression sleeve 23 in an upperposition. The interengaging splines 29 on the compression sleeve 23 andexpander sleeve 28 maintain the cone 30 in spaced relation to the slips34.

The packer is set in the casing C as shown in FIGS. 2A-2D. After thepacker is halted, the pipe string T is elevated slightly and thenlowered while holding right-hand torque. This will disconnect the lug 52on the drag assembly 37 from the jay-slot 53 on the mandrel 11. The dragblocks 40 hold the drag assembly 37 motionless in the casing C. As themandrel 11 is lowered, the expander cone 30 moves downwardly behind theslip heads 43, and the coacting inclined surfaces 36 and 31 cause theslips to be shifted outwardly into gripping contact with the well casingC. With the slip set, the packer is in position and the mandrel 11 canbe moved upwardly and downwardly during installation of surfaceequipment without moving the packer in either direction.

When the mandrel 1 1 has been moved downwardly to a sufficient extent,the upper shoulder 68 will engage the drive ring 66 and force the valvesleeve 62 downwardly until the seals 63 engage the seal surface 64 toclose off the bypass ports 60. The upper end of the coil spring 72 inengaged by the collar 70 and the spring is compressed to provide anupward bias force on the valve sleeve 62. As the mandrel lugs 19 enterthe jay-slots 18, the mandrel 11 is kicked or turned slightly to theleft so that the lugs engage in the closed portions 21 of the jay-slots21 in the locking sleeve 17. As the weight of the pipe string '1 isapplied to the mandrel 11, the upper abutment 22 is ad vanced relativelydownwardly toward the lower abutment 26 to compress and expand thepacking elements 24 into sealing contact with the well casing C as shownin FIG. 2C. A sufficient amount of the weight of the pipe string T isslacked off on the mandrel 11 to ensure the retention of a pack-offunder expected pressure conditions.

In the event that the pressure of fluids below the packer 10 shouldexceed the pressure of fluids in the annulus above the packer, thegreater pressure is communicated by the bypass passage 59 and theclearance spaces 95 and 94 to the upper face of the expander piston 80to force the expander assembly 79 downwardly and slips 76 outwardly asshown in FIG. 2D. The slip teeth 77 grip the casing to anchor the anchorbody 12 and thus the packing 24 against upward movement. The greaterfluid pressure can not move the mandrel 11 upwardly and inadvertentlyopen the bypass passage 59 because of the mechanical interlock providedby the lugs 19 and the jay-slots 18. As previously explained, the valvesleeve 62 is balanced with respect to fluid pressure so that pressuredoes not tend to move it vertically in either direction.

To unseat the packer 10, the mandrel 11 is torqued by the pipe string Tto the right and then lifted. This manipulation will release the lugs 19from the jay-slots 18 and enable the mandrel 11 to be elevated. Asdownward force is removed from the valve sleeve 62, the coil spring 72will force the valve sleeve upwardly to open the bypass passage 59 tothe well an nulus above the packer to equalize pressures across thepacking elements 24. In the event that pressure below the packer isgreater at this point, equalization will occur without retracting theholddown slips 76 so that the packer remains firmly anchored. When themandrel 11 has been elevated sufficiently, the lower shoulder 67 willengage the drive ring 66 and force the seal sleeve 69 upwardly until theseal sleeve shoulder 90 engages the shoulder 91 on the expander piston80 to lift it and retract the slips 76. As compressive force is relievedon the packing elements 24, theywill inherently retract. The jay-slot 53at the bottom end of the mandrel 11 will automatically interengage withthe lug 52 on the drag assembly 37 to lock the packer parts in retractedconditions.

The relatively long travel distance of the mandrel 11 relative to theanchor body 12 and compression sleeve 23 provides a number ofadvantages. For example, when the packer 10 is used as a productiontool, the packer can be properly located and the pipe string T raisedand lowered at the surface during installation of a Christmas tree orflow head without disturbing the setting elevation of the packer 10. Inthis manner, the long stroke of the mandrel 11 compensates for spacingout procedures. Also, the mandrel travel can be used in a manner similarto a bumper sub to provide a jarring action to help free the packer 10in the event that is should become stuck or lodged in the casing.

A modified form of the present invention is illustrated in FIGS. 3A and38, however only the upper portion of the packer 1 10 is shown tosimplify the description, the lower portion being substantiallyidentical to, or an equivalent of, the structural arrangement shown inFIGS. 1C and 1D. In this embodiment, the mandrel 111 is telescopicallydisposed within an anchor body 112 having its lower end connected to anupper abutment ring 122 and to a compression sleeve 123. The sleeve 123carries elastomeric packing elements 124 and spacers 125. The uppersection 113 of the anchor body 112 is closed by a cap 115 that is sealedwith respect to the mandrel 111 by a seal ring 116. In similar manner tothe previously disclosed embodiment, a locking sleeve 117 on the anchorbody 112 has jay-slots 118 with inclined walls 121 and a closed channel121, which are cooperable with lugs 119 on the mandrel collar 120 tomechanically lock the mandrel 111 in its lower position with respect tothe anchor body.

A holddown slip and expander assembly 179 includes slip elements 176received in windows 175 in the anchor body 112. The slip elements 176are adapted to be expanded by a downwardly moveable expander piston 180having expander inserts 181 secured on to stepped wall surfaces thereofby screws 182. The inserts 181 are slidably coupled to the slips 176 bydovetail spline and groove structures 184. The slip elements 176 arealso guided radially outwardly by tongues 186 that fit within grooves187 in a thickened section 188 of the anchor body section 113. The slipelements 176 have teeth 177 adapted to bite into and grip a well casingwall to anchor against upward movement.

A bypass passage 159 extends along the mandrel 111 and terminates inradial ports 161 in communication with the well annulus above thepacking 124. The ports 161 are open during running and retrieving, andare closed off by a valve head 162 carried by a shifting sleeve 172. Thevalve head 162 has spaced seals 163 and 163 that engage seal surfaces164 and 164' when the valve head is moved downwardly into spanningrelation to the ports 161 as the packer 110 is set. The valve head 162is fixed on the shifting sleeve 172 by virtue of its mounting between anupwardly facing exterior shoulder 165 and a snap ring 166. A biasingspring 167 surrounds the shifting sleeve 172 above the valve head 162,the upper end of the spring engaging a fixed ring 168, the lower end ofthe spring engaging a slidable ring 169. The slidable ring 169 isaligned for engagement with a shoulder 170 on the anchor body section114 when the valve head 162 is moved downwardly to closed position. Insuch position, the spring 167 is compressed and exerts an upwardlydirected bias force on the shifting sleeve 172 and valve head 162tending to return it to its upper open position.

The valve head 162 and shifting sleeve 172 are held in the upperposition as shown in FIG. 3B through engagement of an inwardly thickenedsection 190 on the shifting sleeve 172 with an outwardly extendingshoulder 191 on the mandrel 111. To move the valve head 162 to closedposition, a vertically spaced shoulder 192 is provided on the mandrel111 and is adapted to engage the shoulder 193 on the thickened section190. Such interengagement will cause the sleeve 172 and head 162 to becarried downwardly with the mandrel 111 until the head spans the ports161 to block communication between bypass passage 159 and the wellannulus.

The holddown slip and expander assembly 179 is hydraulically operated bya greater pressure of fluids either in the well bore below the packer110 or in the annulus above the packing elements 124 as follows. Theexpander piston is sealed with respect to the inner wall of the anchorbody section 113 by a seal ring 194, andwith respect to the inwardlyextending portion 188 thereof by a seal ring 195. A pressurecommunicating path to the upwardly facing transverse surface of thepiston 180 is provided by the annular clearance 196 between the pistonand the mandrel 111, by the clearance 197 between the shifting sleeve 72and the mandrel, and by radial ports 198 through the wall of the sleeve172 below the valve head 162. The ports 198 communicate with the bypasspassage 159 which is open to the well bore below the packer 110 asdescribed with reference to FIG. 1C. The downwardly facing transversesurfaces of the expander piston 180 located between the seals 195 and194 are exposed to the pressure of fluids in the well annulus via thewindows 175 in the anchor body 112. Accordingly, when the valve head 162is in closed position, a greater fluid pressure below the packer 110will act downwardly on an area equal to the difference in transverseareas circumscribed by the seals 194 and 195 to force the expanderpiston 180 downwardly and the slip elements 176 outwardly. Conversely, agreater fluid pressure in the annulus will retract the slip elements176.

During running and retrieving, the slip elements 176 are positively heldretracted because the upper end surface 199 of the shifting sleeve 172engages the lower end surface 200 of the expander piston 180 to preventdownward movement of the expander piston. When the mandrel 111 is moveddownwardly, however, to close the valve head 162 and set the packingelements 124, ample clearance is provided between the end surfaces 199and 200 to enable operation of the expander piston 180.

It should be noted that when the valve head 162 is in closed position,fluid pressure forces thereon are balanced because the seal surfaces 164and 164 circumscribe equal transverse areas. Thus fluid pressures cannotact to move the valve head 162 or the shifting sleeve 172 vertically. Toopen the valve head 162, the mandrel 111 is lifted upwardly. Normallythe coil spring 167 will force the valve head 162 upwardly and enableequalization of pressures above and below the packing elements 124before the holddown slips 176 are retracted. In any event, sufficientupward movement of the mandrel 111 will bring the shoulder 191 againstthe shifting sleeve shoulder 190 to elevate the sleeve and the expanderpiston 180 and return the parts to running-in positions.

As with the case of the embodiment disclosed in FIGS. 1

and 2, the packer shown in FIG. 3 has a long stroke mandrel, a balancedvalve, and a mechanical interlock to lock the mandrel in its lowerposition where the bypass passage 159 is closed. Since various changesor modifications may be made in the disclosed embodiments withoutdeparting from the inventive concepts involved, it is the aim of theappended claims to cover all such changes or modifications fallingwithin the true spirit and scope of the present invention.

lclaim:

1. A well packer apparatus comprising: an anchor body; a mandrel movablewithin said anchor body between an upper position and a lower positionrelative thereto; normally retracted slip means mounted on said anchorbody and adapted to be shifted to expanded position; hydraulicallyoperable means movable between an upper position for retracting saidslip means and a lower position for expanding said slip means; packingmeans surrounding said mandrel and including packing elements forsealing off a well bore; a fluid passage space extending between saidpacking means and said mandrel and between locations in communicationwith the well bore above and below said packing means; valve means onsaid mandrel movable longitudinally relative to said mandrel and to saidanchor body and between an upper open position and a lower closedposition with respect to said fluid passage space; first means coactingin the upper position of said mandrel for preventing downward movementof said hydraulically operable means to retain said slip mans inretracted positions; and second means coacting in the lower position ofsaid mandrel for moving said valve means to said closed position.

2. The well packer apparatus of claim 1 further including means forproviding an upwardly directed bias force on said valve means in saidclosed position.

3. The well packer apparatus of claim 1 wherein said first meansincludes a shoulder on said mandrel engageable with said valve means tohold said valve means in its upper position, said valve means having ashoulder engaging said hydraulically operable means to hold saidhydraulically operable means in its upper position.

4. The well packer apparatus of claim 1 wherein said second meansincludes a shoulder on said mandrel engageable with said valve means toforce said valve means downwardly.

S. A well packer apparatus comprising: an anchor body; a mandrel movablewithin said anchor body between an upper position and a lower positionrelative thereto; packing means surrounding said mandrel and adapted toseal off a well bore; normally retracted slip means mounted on saidanchor body and adapted for outward movement relative to said anchorbody between extended and retracted positions; hydraulically operablemeans for moving said slip means outwardly; a fluid passage spaceextending longitudinally between said packing means and said mandrelbetween locations in communication with the well bore above and belowsaid packing means; valve means on said mandrel and movable within saidanchor body between an upper open position and a lower closed positionwith respect to said fluid passage space; and oppositely disposedshoulders on said mandrel in spaced relation to one another and adaptedfor alternate engagement with said valve means, one of said shoulderspositioning said valve means in open position in the upper position ofsaid mandrel and the other of said shoulders positioning said valvemeans in closed position in the lower position of said mandrel.

6. The well packer apparatus of claim 6 further including coengageablemeans coacting at the upper position of said mandrel for preventingoperation of said hydraulic means to retain said slip means in retractedpositions.

- 7. The well packer apparatus of claim 7 wherein said coengageablemeans includes a shoulder surface on said valve means engageable with ashoulder surface on said hydrauli cally operable means.

8. The well packer apparatus of claim 6 wherein said hydraulicallyoperable means includes expander means movable between an upper positionfor retracting said slip means and a lower position for expanding saidslip means, and further including coengageable means coacting at theupper position of said mandrel for holding said expander means in itsupper position to positively retain said slip means in retractedposition.

9. The well packer apparatus of claim 9 wherein said coengageable meansincludes an upwardly facing shoulder surface on said valve meansengageable with a downwardly facing surface on said expander means.

10. A well packer apparatus comprising: an anchor body; a mandrelmovable within said anchor body between an upper position and a lowerposition relative thereto; packing means surrounding said mandrel andadapted for sealing off a well bore; bypass means for bypassing fluidthrough said packing means; sleeve valve means movable relative to saidanchor body and said mandrel and between an upper open position and alower closed position with respect to said bypass means, said mandrelhaving longitudinally spaced, oppositely disposed shoulder surfacesalternately engageable with said sleeve valve means for positioning saidsleeve valve means in open or closed position; slip means mounted onsaid anchor body and movable between an inner retracted position and anouter extended position; hydraulic means in said anchor body movablebetween an upper position for retracting said slip means and a lowerposition for extending said slip means; a seal sleeve extending alongsaid mandrel and connected to said sleeve valve means, said hydraulicmeans including an expander piston sealingly slidable on said anchorbody and said seal sleeve; means for feeding the pressure of fluids insaid bypass means along a path interiorly of said valve sleeve means-andsaid seal sleeve to a location above said expander piston to force saidexpander piston downwardly; and means coacting in the upper position ofsaid mandrel for holding said expander piston in its upper position toselectively prevent outward movement of said slip means, said holdingmeans being released by downward movement of said mandrel.

11. The well packer apparatus of claim 10 wherein said bypass meansterminates at a location above said packing means in port meansextending laterally through the wall of said anchor body, said sleevevalve means and anchor body having seal means coengageable below saidport in the closed position of said sleeve valve means.

12. The well packer apparatus of claim 10 further including bias meansfor providing an upward force on said sleeve valve means at the closedposition of said sleeve valve means.

13. The well packer apparatus of claim 10 further including lockingmeans for securing said mandrel to said anchor body in said lowerposition.

14. The well packer apparatus of claim 13 wherein said locking meansincludes lug means on said mandrel cooperable with channel means on saidanchor body in the lower position of said mandrel.

15. A well packer apparatus comprising: an anchor body; a mandrelmovable within said anchor body between an upper position and a lowerposition relative thereto; packing means surrounding said mandrel andadapted to seal off a well bore; by pass means for bypassing fluidthrough said packing means between locations above and below saidpacking means, said bypass means terminating at the location above saidpacking means in laterally extending port means through the wall of saidanchor body; valve means including an annular member adapted formovement between an upper open position and a lower closed position withrespect to said port means, said annular member in said lower positionspanning and closing off said port means; longitudinally spaced andoppositely disposed shoulder surfaces on said mandrel alternatelyengageable with said valve means for moving said annular member betweenopen and closed positions; slip means on said anchor body movablebetween inner retracted positions and outer extended positions;hydraulically operable means movable between an upper position forretracting said slip means and a lower position for extending said slipmeans; and coengageable means coacting in the upper position of saidmandrel for holding said hydraulically operable means in its upperposition to prevent outward movement of said slip means.

16. The well packer apparatus of claim 15 further including releasablemeans on said mandrel and anchor body for securing said mandrel to saidanchor body in said lower position where said valve means is in closedposition.

17. The well packer apparatus of claim 16 wherein said hydraulicallyoperable means includes a piston member sealingly slidable in cylindermeans in said anchor body, said coengageable means including opposedshoulder surfaces on said piston member and said valve means.

18. The well packer apparatus of claim 17 further including means forfeeding the pressure of fluids in said bypass means along said mandrelinteriorly of said valve means and piston member to a location in saidcylinder means above said piston member.

19. The well packer apparatus of claim 16 further including bias meansfor applying an upward force to said valve means in its closed positionto assist in moving it to open position.

20. The well packer apparatus of claim 19 wherein said bias meanscomprises a spring surrounding said valve means above said annularmember, the upper end of said spring being fixed to said valve means,the lower end of said spring being adapted to engage a shoulder on saidanchor body to compress aid spring during movement of said valve meansto closed position.

1. A well packer apparatus comprising: an anchor body; a mandrel movablewithin said anchor body between an upper position and a lower positionrelative thereto; normally retracted slip means mounted on said anchorbody and adapted to be shifted to expanded position; hydraulicallyoperable means movable between an upper position for retracting saidslip means and a lower position for expanding said slip means; packingmeans surrounding said mandrel and including packing elements forsealing off a well bore; a fluid passage space extending between saidpacking means and said mandrel and between locations in communicationwith the well bore above and below said packing means; valve means onsaid mandrel movable longitudinally relative to said mandrel and to saidanchor body and between an upper open position and a lower closedposition with respect to said fluid passage space; first means coactingin the upper position of said mandrel for preventing downward movementof said hydraulically operable means to retain said slip mans inretracted positions; and second means coacting in the lower position ofsaid mandrel for moving said valve means to said closed position.
 2. Thewell packer apparatus of claim 1 further including means for providingan upwardly directed bias force on said valve means in said closedposition.
 3. The well packer apparatus of claim 1 wherein said firstmeans includes a shoulder on said mandrel engageable with said valvemeans to hold said valve means in its upper position, said valve meanshaving a shoulder engaging said hydraulically operable means to holdsaid hydraulically operable means in its upper position.
 4. The wellpacker apparatus of claim 1 wherein said second means includes ashoulder on said mandrel engageable with said valve means to force saidvalve means downwardly.
 5. A well packer apparatus comprising: an anchorbody; a mandrel movable within said anchor body between an upperposition and a lower position relative thereto; packing meanssurrounding said mandrel and adapted to seal off a well bore; normallyretracted slip means mounted on said anchor body and adapted for outwardmovement relative to said anchor body between extended and retractedpositions; hydraulically operable means for moving said slip meansoutwardly; a fluid passage space extending longitudinally between saidpacking means and said mandrel between locations in communication withthe well bore above and below said packinG means; valve means on saidmandrel and movable within said anchor body between an upper openposition and a lower closed position with respect to said fluid passagespace; and oppositely disposed shoulders on said mandrel in spacedrelation to one another and adapted for alternate engagement with saidvalve means, one of said shoulders positioning said valve means in openposition in the upper position of said mandrel and the other of saidshoulders positioning said valve means in closed position in the lowerposition of said mandrel.
 6. The well packer apparatus of claim 6further including coengageable means coacting at the upper position ofsaid mandrel for preventing operation of said hydraulic means to retainsaid slip means in retracted positions.
 7. The well packer apparatus ofclaim 7 wherein said coengageable means includes a shoulder surface onsaid valve means engageable with a shoulder surface on saidhydraulically operable means.
 8. The well packer apparatus of claim 6wherein said hydraulically operable means includes expander meansmovable between an upper position for retracting said slip means and alower position for expanding said slip means, and further includingcoengageable means coacting at the upper position of said mandrel forholding said expander means in its upper position to positively retainsaid slip means in retracted position.
 9. The well packer apparatus ofclaim 9 wherein said coengageable means includes an upwardly facingshoulder surface on said valve means engageable with a downwardly facingsurface on said expander means.
 10. A well packer apparatus comprising:an anchor body; a mandrel movable within said anchor body between anupper position and a lower position relative thereto; packing meanssurrounding said mandrel and adapted for sealing off a well bore; bypassmeans for bypassing fluid through said packing means; sleeve valve meansmovable relative to said anchor body and said mandrel and between anupper open position and a lower closed position with respect to saidbypass means, said mandrel having longitudinally spaced, oppositelydisposed shoulder surfaces alternately engageable with said sleeve valvemeans for positioning said sleeve valve means in open or closedposition; slip means mounted on said anchor body and movable between aninner retracted position and an outer extended position; hydraulic meansin said anchor body movable between an upper position for retractingsaid slip means and a lower position for extending said slip means; aseal sleeve extending along said mandrel and connected to said sleevevalve means, said hydraulic means including an expander piston sealinglyslidable on said anchor body and said seal sleeve; means for feeding thepressure of fluids in said bypass means along a path interiorly of saidvalve sleeve means and said seal sleeve to a location above saidexpander piston to force said expander piston downwardly; and meanscoacting in the upper position of said mandrel for holding said expanderpiston in its upper position to selectively prevent outward movement ofsaid slip means, said holding means being released by downward movementof said mandrel.
 11. The well packer apparatus of claim 10 wherein saidbypass means terminates at a location above said packing means in portmeans extending laterally through the wall of said anchor body, saidsleeve valve means and anchor body having seal means coengageable belowsaid port in the closed position of said sleeve valve means.
 12. Thewell packer apparatus of claim 10 further including bias means forproviding an upward force on said sleeve valve means at the closedposition of said sleeve valve means.
 13. The well packer apparatus ofclaim 10 further including locking means for securing said mandrel tosaid anchor body in said lower position.
 14. The well packer apparatusof claim 13 wherein said locking means includes lug means on saidmandrel cooperable with channel means on said anchor body in the lowerposition of said mandrel.
 15. A well packer apparatus comprising: ananchor body; a mandrel movable within said anchor body between an upperposition and a lower position relative thereto; packing meanssurrounding said mandrel and adapted to seal off a well bore; by passmeans for bypassing fluid through said packing means between locationsabove and below said packing means, said bypass means terminating at thelocation above said packing means in laterally extending port meansthrough the wall of said anchor body; valve means including an annularmember adapted for movement between an upper open position and a lowerclosed position with respect to said port means, said annular member insaid lower position spanning and closing off said port means;longitudinally spaced and oppositely disposed shoulder surfaces on saidmandrel alternately engageable with said valve means for moving saidannular member between open and closed positions; slip means on saidanchor body movable between inner retracted positions and outer extendedpositions; hydraulically operable means movable between an upperposition for retracting said slip means and a lower position forextending said slip means; and coengageable means coacting in the upperposition of said mandrel for holding said hydraulically operable meansin its upper position to prevent outward movement of said slip means.16. The well packer apparatus of claim 15 further including releasablemeans on said mandrel and anchor body for securing said mandrel to saidanchor body in said lower position where said valve means is in closedposition.
 17. The well packer apparatus of claim 16 wherein saidhydraulically operable means includes a piston member sealingly slidablein cylinder means in said anchor body, said coengageable means includingopposed shoulder surfaces on said piston member and said valve means.18. The well packer apparatus of claim 17 further including means forfeeding the pressure of fluids in said bypass means along said mandrelinteriorly of said valve means and piston member to a location in saidcylinder means above said piston member.
 19. The well packer apparatusof claim 16 further including bias means for applying an upward force tosaid valve means in its closed position to assist in moving it to openposition.
 20. The well packer apparatus of claim 19 wherein said biasmeans comprises a spring surrounding said valve means above said annularmember, the upper end of said spring being fixed to said valve means,the lower end of said spring being adapted to engage a shoulder on saidanchor body to compress aid spring during movement of said valve meansto closed position.